We have lymph nodes in that area. My guess is that it is a swollen lymph node from being sick. This is what is supposed to happen. That is part of the bodies defense system. Are you talking outside your neck? Or in your throat though? I would not panic or anything. You are seeing an ENT and they are good about following up about concerning issues. If they are not concerned, that is a good sign. Second opinions may confirm this though.
Large thyroid nodules or goiter can cause that sensation and the lump as well: https://www.mayoclinic.org/diseases-conditions/thyroid-nodules/symptoms-causes/syc-20355262
It isn't possible to determine whether the issue is caused by thyroid or tonsilitis without physical examination and further testing. Are you taking any medication for tonsilitis or your thyroid nodules?